1. Field of the Invention
This invention relates generally to transducer suspension systems and more particularly to a suspension system which compensates for actuator arm bending.
2. Description of the Prior Art
Direct access storage devices (DASD), or disk drives, store information on concentric tracks of a rotatable magnetic recording disk. A magnetic head or transducer element is moved from track to track to record and reads the desired information. Typically, the magnetic head is positioned on an air bearing slider which flies above the surface of the disk as the disk rotates. In some recently proposed disk drives, the slider (or carrier) rides on a liquid film or bearing on the disk. A suspension assembly connects the slider to a rotary or linear actuator. The suspension assembly provides support for the slider.
Examples of suspension systems are shown in the following references: U.S. Pat. No. 5,546,649, issued Aug. 20, 1996, to Shimanuki; U.S. Pat. No. 5,475,549, issued Dec. 12, 1995, to Marder et al; U.S. Pat. No. 5,461,524, issued Oct. 24, 1995, to Jurgenson; U.S. Pat. No. 5,459,921, issued Oct. 24, 1995, to Hudson et al; U.S. Pat. No. 5,444,587, issued Aug. 22, 1995, to Johnson et al; U.S. Pat. No. 5,299,082, issued Mar. 29, 1994, to Ananth et al; U.S. Pat. No . 5,260,847, issued Nov. 9, 1993, to Basehore et al; U.S. Pat. No . 5,187,626, issued Feb. 16, 1993, to Hopkins et al; U.S. Pat. No . 5,172,286, issued Dec. 15, 1992, to Jurgenson; U.S. Pat. No. 5,014,142, issued May 7, 1991, to Nakanishi et al; U.S. Pat. No. 4,875,117, issued Oct. 17, 1989, to Slezak et al; U.S. Pat. No. 4,870,525, issued Sept. 26, 1989, to Wong et al; U.S. Pat. No. 4,829,395, issued May 9, 1989, to Coon et al; U.S. Pat. No. 4,796,122, issued Jan. 3, 1989, to Levy et al; U.S. Pat. No. 4,346,416, issued Aug. 24, 1982, to Riggle et al; and IBM Technical Disclosure Bulletin Vol. 37, No. 12, Dec. 1994, page 181.
The suspension is attached to an actuator arm of the actuator motor. The actuator motor is used to move the transducer head from track to track on the recording disk. High capacity disk drives typically have a plurality of recording disks arranged in a disk stack. Actuator arms which are located between two disks typically have two suspensions attached, one to access the disk surface above and one to access the disk surface below. However, actuator arms on each end of the stack (top and bottom arms) have only one suspension attached which accesses a single disk surface. Disk drives which have a single disk typically have an actuator arm above the disk and an actuator arm below the disk, each having a single suspension.
The inventors have discovered that in multiple disk files the transducer heads on the actuator arms having a single suspension have higher data error rates than transducer heads on actuator arms having two suspensions. This invention was designed to solve this problem.